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I shoot mostly landscapes and am often annoyed when bright sky bleeds into the leaf silhouettes.

Would a graduated filter help? Any other ideas?

I have had this problem with my D90, Gf1 and now D800e.

Is it just a Dynamic Range issue?

enter image description here

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    This sort of question is in general much easier to answer if you can give an example of the problem you're seeing. I know that new users can't directly add photos, but you should be able to link to one elsewhere.
    – Philip Kendall ♦
    Jul 15 '13 at 7:59
  • Is the effect the same throughout the image or worse near the edges/corners?
    – Michael C
    Jul 15 '13 at 12:20
  • I'm confused by the edit here: @Ray, are you also user21041? If not, why are we adding photos from one user to another user's post.
    – Philip Kendall ♦
    Jul 18 '13 at 20:45
  • @philip Ray posted the photo here that I linked to on flickr because I don't have the posts under my belt, and kheric posted a Sigma Foveon example. Thanks!
    – Doctor Atomo
    Jul 19 '13 at 3:39
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    @PhilipKendall--OP had posted a link to these pictures in a comment against one of the answers. I just did the embed.
    – Ray
    Jul 19 '13 at 11:39
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Difficult to say without seeng an example. But taken from the few describing words it sounds very much like a dynamic range issue. If so then a gradual ND filter could help - depending on the concrete composition of the image - or you apply some HDR techique.

HDR, if properly done, does not need to thave this horrible ovedone "HDR style". Those pictues can actually quite nice in a way that only experts can say whether it is based on an HDR or not.

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  • "...horrible overdone "HDR Style"." I call them Technicolor rainbows of vomit.
    – Michael C
    Jul 15 '13 at 12:19
  • I agree this is a dynamic range problem. HDR is the best solution, as with an ND filter you will underexpose the branches in the trees resulting in loss of detail. Also, only 'full on' HDR done in software like Photomatix will do; basic exposure blending will be a bitch masking out every branch on every tree.
    – ElendilTheTall
    Jul 15 '13 at 12:38
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It may be chromatic aberration that you see if there are any purple/green fringing around leaves. That generally occur in high-contrast objects. If it's this one you can fix this by shooting RAW and than selection "Remove chromatic aberration" in Adobe Camera Raw software or DxO Optics Pro 8.

If by blending, you mean it's not balanced to the ground than you can put on a soft graduate 0.6 neutral density filter(I use B+W and it's great) dark side up on your lens. This will balance the darker ground to the brighter sky so you won't have any problems.

Instead of ND lens you can choose to shoot RAW and then with Camera Raw imitate ND filter again. And/or lessen highlights, brighten shadows and you're set again. Not as effective as a ND filter but it'll do.

If you post a sample photo it'll be easier to help.

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  • @Michael Clark @ Hermann Klecker, Herman said "Horrible over done HDR", Michael said "Technicolor rainbows of vomit" I call it "Toxic Sky Syndrome, Lol. I don't mind HDR if it helps correct the low DR compared to your eye, or possibly in some artistic situations, but the overcooked stuff is pretty terrible!
    – Doctor Atomo
    Jul 18 '13 at 6:38
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If I understand what you're indicating then it's the slightly darker blue of the sky seen between the branches and leaves of the trees. This isn't entirely chromatic aberration (although that could exist too in high contrast areas), but from your example it looks like an effect of the color filter array on the sensor, the demosaic/interpolation algorithm, as well as the relative light intensity in those areas.

What a color filter array does is provide multiple colors for light to pass through, usually giving green a greater opportunity. Here is a basic illustration of how it works:

CMOS technology
(source: img-dpreview.com)

The Red, Green and Blue inputs, with the composite result:

CMOS red example image
(source: img-dpreview.com)
CMOS green example image
(source: img-dpreview.com)
CMOS blue example image
(source: img-dpreview.com)
CMOS composite example image
(source: img-dpreview.com)

The reason this is done is because a digital image sensor can only be turned on or off by a ray of light - which is effectively black or white. After passing through a color filter array each pixel on an image sensor effectively has a single color value. The image then needs to be demosaiced and/or interpolated, which means to have information constructed from the known information recorded.

Okay, great, what's this have to do with branches and blue skies?

In your case, the sensor is generating color values for the ones recorded in and around the leaves and branches. Blue is the color of the sky, but the intensity (brightness) of the blue is diminished from the surrounding leaves and branches (which are comparatively dark and block some of the light). As a result, you get a slightly darker shade of blue in those areas.

Blame the demosaic/interpolation algorithm your camera uses (if you record as JPEG) or your software uses (if you record in RAW format). Maybe taking digital photographs with something like a Foveon sensor (Sigma) camera or some other technology will work better at preventing this from happening as noticeably. You'll still need to contend with relative light intensity and then chromatic aberration if applicable (look at high contrast areas like in the example below taken with a Foveon sensor), but the issue won't be as pronounced:

Foveon image of tree leaves from below

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  • Thanks for the tutorial kheric :) Hm. Now that you mention it the sky IS darker between the branches and where the "Color Bleed" occurs, but what I'm talking about is the blue covering the branches and leaves as seen in the large view here: tinyurl.com/colorbleed Foveon! Well the price has come down since the DP1 was released... it would be fun, but next purchase is probably a Sigma 35mm 1.4 HSM lens :) The Foveon image has the colorbleed too. Maybe not as bad?
    – Doctor Atomo
    Jul 19 '13 at 3:53
  • Do you use a Fovean sensor camera? And if so what are your experiences with it? What I remember from the DPR review when thew SD1 first came out it was promising but expensive and rough around the edges. The five minutes on reading Amazon Reviews left me with the impression that the technology is still immature.
    – Doctor Atomo
    Jul 19 '13 at 6:20
  • I also really need the mega pixels as I love landscapes and always want wider, wider, more more! The price point and usability of the D800e is just... lets just say I can justify (to myself at least) the expense, when comparing to the medium format competition, which... I would have to do a LOT more justification, lol! I was beginning to outgrow the 12mp of the stellar D90 I sold to a photography student who loves it!
    – Doctor Atomo
    Jul 19 '13 at 6:21
  • So, I would love a Fovean type sensor with the DR and build of the D800e but it would need a 108MP sensor since you need to divide by three to get actual MP output :D Oh yeah, and it would have to cost $3000. $3000. Seriously though, how do you like your Foveon if you own one?
    – Doctor Atomo
    Jul 19 '13 at 6:23
  • Well, given how many factors are possible to add up to this effect, the last one (after sensor design, conversion algorithms, and chromatic aberration) could be dynamic range. I didn't mention this before as the D800 has an incredible dynamic range and it seems unlikely. You can simulate the effect artificially by using a levels tool found in most photo apps and moving the right most slider inward past the bright data. This effectively clips the subtle shades progressing toward white and makes them only white.
    – kheric
    Jul 19 '13 at 14:27
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Your text isn't very clear. Also you didn't put a photo/crop to show the effect.

bright sky "bleeds" into the leaf 'silhouettes'... hmmm...

Perhaps do you want to say blends ??

Perhaps it is a phenomenon like this?

http://en.wikipedia.org/wiki/File:Chromatic_aberration_1_14_2009.jpg

If yes, then it is called Chromatic Aberration.

One of the biggest factors of influence is the quality of the lens. If you can get/afford/if exist, try to get a better lens. Btw, what lens do you have?

Also, yes, an graduated ND filter helps. OTOH, you can try also with a CPL filter (which, for our discussion, acts also like a weak graduated ND filter) but it has also other properties which are useful for landscape photography (your object of interest).

And as a final note, you can try to remove CAs in post-processing.

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  • Thanks to everyone for the kind answers. Yes, John Thomas it looks like chromatic aberration from the pictures I've seen describing the phenomenon. I deleted the example I was thinking of so I can't post it. I tried to recreate it today but the pictures came out fine, lol. I will attempt try the same subject tomorrow and post an example to my flikr account :) Lens is the Nikon 24-85 3.5 that comes with the D600. It is a good copy and normally exhibits no CA. Just these weird blue leaves when shot against a bright sky...
    – Doctor Atomo
    Jul 16 '13 at 4:01
  • @user21041: (Almost) any lens have CA. There are, of course, apochromatic ones but these are rather rare beasts. See en.wikipedia.org/wiki/Apochromat and dpreview.com/forums/thread/3057500 ...also, perhaps we should note that CA appears mostly at the edges between two areas with strong contrast (bright/dark)
    – John Thomas
    Jul 16 '13 at 7:44
  • Ok, I had time to get a couple photos exhibiting a minor example of the effect :) flickr.com/photos/58629523@N02/sets/72157634680474859 – –
    – Doctor Atomo
    Jul 18 '13 at 1:08
  • @DoctorAtomo: Yes, it is a classical example of CA. You can 'cure' it through the above recommendations. Also, you can avoid to shoot against harsh light and 'simulate' it in post processing by increasing contrast etc.
    – John Thomas
    Jul 19 '13 at 7:57
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... weird blue leaves when shot against a bright sky... – Doctor Atomo

I doubt the blue leaves are caused by the Bayer matrix on your sensor because an image produced by a Foveon sensor also has the same effect. I suspect they are chromatic aberration caused by your lens or diffraction of skylight around the leaves. The resolution of the sample images is too low to tell clearly.

... bright sky bleeds into the leaf silhouettes...

Problems that match this description may include:

  1. JPEG artifacts. Try using higher resolution and "Fine" or "Super Fine" JPEG settings on your camera.
  2. Chromatic aberration or color fringing.
  3. Halos or glow from spherical aberration.

Chromatic aberration, color fringing, and spherical aberration are often worst when lenses are used wide open.

  • Their effects can be reduced by closing the aperture a stop or two.

  • You may attempt to use post processing software, as Kursat and John Thomas suggest. Hugin includes utilities tca_correct and fulla for this task.

  • You may need to try a different lens.

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The safe answer is that it is a combination of over-exposure and chromatic abberation, which is then very visible over the black leaves.

But there may be more to it than that. Camera sensors are not colorimetrically identical to human eyes, they may see a bit into the infrared and/or ultraviolet spectrum too. IR light may add to the red channel, UV light may add to the blue channel. On such a high contrast scene even a little bit may be enough to do harm. And the lens has been corrected for chromatic abberation over the visible spectrum, but outside that corrected range the errors grow quickly. See the last figure in https://en.wikipedia.org/wiki/Achromatic_lens .

So, thinking that a little bit of UV sensitivity may manifest as a significant blue or violet glare, I am experimenting with a UV filter to see if I can get the CA for this sort of situation under control. It has to be a filter with a deliberate cutoff below ~450 nm. This will be on a Tamron 45mm/1.8 SP lens, which is known for having CA issues.

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I think the problem does lie with the dynamic range. Using the photo above as an example I don't see how a graduated filter helps as the sky is inter twinned. I would try a polarising filter

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Usually cameras have software to deal with the worst effects of longitudinal aberration (the effect when near-UV visible and near-visible UV light registered by the sensor have a different focus plane than longer wavelengths). However, for this to work, the sky must not be blown out (or the camera has no way to really guess the brightness and hue of the sky). A polariser can help with some parts of the sky (not everything is polarised) by reducing the overall sky brightness. Even then, correct exposure will most likely render the branches underexposed. Like with many high-contrast backlit situations, a fill flash may help defuse the situation. The danger of the flash dominating the scene is basically non-existent but it may still reduce the dynamic range slightly.

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